The role of adenosine A1 and A3 receptors in mediating cardioprotection has been studied predominantly in rabbits, yet the pharmacological characteristics of rabbit adenosine A1 and A3 receptor subtypes are unknown. Thus, the rabbit adenosine A3 receptor was cloned and expressed, and its pharmacology was compared with that of cloned adenosine A1 receptors. Stable transfection of rabbit A1 or A3...

Four adenosine receptors have been cloned and characterized from several mammalian species. The receptors are named adenosine A(1), A(2A), A(2B), and A(3). The A(2A) and A(2B) receptors preferably interact with members of the G(s) family of G proteins and the A(1) and A(3) receptors with G(i/o) proteins. However, other G protein interactions have also been described. Adenosine is the preferred ...

Acute activation of Galpha(i/o)-coupled D2 dopamine receptors inhibits A2A adenosine receptor stimulation of adenylate cyclase. This antagonistic interaction between D2 dopamine and A2A adenosine receptors has been well documented; however, the effects of persistent activation of D2 dopamine receptors on subsequent A2A adenosine receptor signaling have not been explored. The present study inves...

Gliomas are the most common and aggressive primary tumors in central nervous system. The nucleoside adenosine is considered to be one major constituent within tumor microenvironment. level mainly depends on two enzymatic activities: 5′-nucleotidase (5′NT or CD73) that synthesizes from AMP, deaminase (ADA) converts into inosine. Adenosine activates specific G-protein coupled receptors named A 1 ...

Adenosine-induced modulation of neuromuscular transmission in young (3-4-week-old) rats was evaluated. Inhibition of adenosine kinase with iodotubercidin (ITU; 10 microM), which is known to induce adenosine release, enhanced the amplitude of evoked end-plate potentials (EPPs) recorded from innervated diaphragm muscle fibers. This facilitatory effect was transformed into an inhibitory one upon b...

The purpose of the present study was to characterize adenosine receptors in human atrial and ventricular myocardium. In isolated electrically driven preparations, adenosine produced "direct" negative inotropic effects in atrial myocardium (AT). In ventricular myocardium (VE), it only had negative inotropic properties when force of contraction had been stimulated with isoprenaline ("indirect" ef...